<ol>
  <li>Specify the start point of the first line segment. You can use the mouse
  or enter a coordinate in the console.</li>
  <li>Specify the endpoint of the first line segment.</li>
  <li>Specify the endpoints of additional line segments. Click the 'Close'
  button in the options tool bar to close the sequence: 
  <br />
  <img width="40" height="40" src="Close.png" />
  <br />If you need to undo a single line segment, you can do so by clicking
  the 'Undo' button: 
  <br />
  <img width="40" height="40" src="Undo.png" /></li>
</ol>
